Abstract
Antiferromagnets are promising platforms for transduction and transmission of quantum information via magnons—the quanta of spin waves—and they offer advantages over ferromagnets in regard to dissipation, speed of response and robustness to external fields. Recently, transduction was shown in a van der Waals antiferromagnet, where strong spin-exciton coupling enables readout of the amplitude and phase of coherent magnons by photons of visible light. This discovery shifts the focus of research to transmission, specifically to exploring the non-local interactions that enable magnon wave packets to propagate. Here we demonstrate that magnon propagation is mediated by long-range dipole–dipole interaction. This coupling is an inevitable consequence of fundamental electrodynamics and, as such, will likely mediate the propagation of spin at long wavelengths in the entire class of van der Waals magnets currently under investigation. Successfully identifying the mechanism of spin propagation provides a set of optimization rules, as well as caveats, that are essential for any future applications of these promising systems.
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Data availability
Source data are provided with this paper and uploaded to Materials Cloud (https://doi.org/10.24435/materialscloud:9x-ds)31.
Code availability
The computer codes used to generate results are provided as the Supplementary Code and uploaded to Materials Cloud (https://doi.org/10.24435/materialscloud:9x-ds)31.
References
Lachance-Quirion, D. et al. Entanglement-based single-shot detection of a single magnon with a superconducting qubit. Science 367, 425–428 (2020).
Pirro, P., Vasyuchka, V. I., Serga, A. A. & Hillebrands, B. Advances in coherent magnonics. Nat. Rev. Mater. 6, 1114–1135 (2021).
Cornelissen, L. J., Liu, J., Duine, R. A., Youssef, J. B. & van Wees, B. J. Long-distance transport of magnon spin information in a magnetic insulator at room temperature. Nat. Phys. 11, 1022–1026 (2015).
Lebrun, R. et al. Tunable long-distance spin transport in a crystalline antiferromagnetic iron oxide. Nature 561, 222–225 (2018).
Lebrun, R. et al. Long-distance spin-transport across the Morin phase transition up to room temperature in ultra-low damping single crystals of the antiferromagnet α-Fe2O3. Nat. Commun. 11, 6332 (2020).
Han, J. et al. Birefringence-like spin transport via linearly polarized antiferromagnetic magnons. Nat. Nanotechnol. 15, 563–568 (2020).
Wei, X.-Y. et al. Giant magnon spin conductivity in ultrathin yttrium iron garnet films. Nat. Mater. 9, 1352–1356 (2022).
Gibertini, M., Koperski, M., Morpurgo, A. F. & Novoselov, K. S. Magnetic 2D materials and heterostructures. Nat. Nanotechnol. 14, 408–419 (2019).
Gong, C. & Zhang, X. Two-dimensional magnetic crystals and emergent heterostructure devices. Science 363, eaav4450 (2019).
Mak, K. F., Shan, J. & Ralph, D. C. Probing and controlling magnetic states in 2D layered magnetic materials. Nat. Rev. Phys. 1, 646–661 (2019).
Jungwirth, T., Marti, X., Wadley, P. & Wunderlich, J. Antiferromagnetic spintronics. Nat. Nanotechnol. 11, 231–241 (2016).
Baltz, V. et al. Antiferromagnetic spintronics. Rev. Mod. Phys. 90, 015005 (2018).
Xing, W. et al. Magnon transport in quasi-two-dimensional van der Waals antiferromagnets. Phys. Rev. X 9, 011026 (2019).
Hoogeboom, G. R. & van Wees, B. J. Nonlocal spin Seebeck effect in the bulk easy-plane antiferromagnet NiO. Phys. Rev. B 102, 214415 (2020).
Kalashnikova, A. M. et al. Impulsive generation of coherent magnons by linearly polarized light in the easy-plane antiferromagnet FeBO3. Phys. Rev. Lett. 99, 167205 (2007).
Satoh, T. et al. Spin oscillations in antiferromagnetic NiO triggered by circularly polarized light. Phys. Rev. Lett. 105, 077402 (2010).
Tzschaschel, C. et al. Ultrafast optical excitation of coherent magnons in antiferromagnetic NiO. Phys. Rev. B 95, 174407 (2017).
Sonin, E. Spin currents and spin superfluidity. Adv. Phys. 59, 181–255 (2010).
Sonin, E. B. Superfluid spin transport in magnetically ordered solids (review article). J. Low Temp. Phys. 46, 436–447 (2020).
Bae, Y. J. et al. Exciton-coupled coherent magnons in a 2D semiconductor. Nature 609, 282–286 (2022).
Scheie, A. et al. Spin waves and magnetic exchange Hamiltonian in CrSBr. Adv. Sci. 9, 2202467 (2022).
Damon, R. & Eshbach, J. Magnetostatic modes of a ferromagnet slab. J. Phys. Chem. Solids 19, 308–320 (1961).
Hurben, M. & Patton, C. Theory of magnetostatic waves for in-plane magnetized anisotropic films. J. Magn. Magn. Mater. 163, 39–69 (1996).
Satoh, T. et al. Directional control of spin-wave emission by spatially shaped light. Nat. Photon 6, 662–666 (2012).
Demokritov, S. O. et al. Bose–Einstein condensation of quasi-equilibrium magnons at room temperature under pumping. Nature 443, 430–433 (2006).
Matsumoto, R. & Murakami, S. Theoretical prediction of a rotating magnon wave packet in ferromagnets. Phys. Rev. Lett. 106, 197202 (2011).
Camley, R. E. Long-wavelength surface spin waves on antiferromagnets. Phys. Rev. Lett. 45, 283–286 (1980).
Lüthi, B., Mills, D. L. & Camley, R. E. Surface spin waves in antiferromagnets. Phys. Rev. B 28, 1475–1479 (1983).
Stamps, R. & Camley, R. Magnetostatic modes in thin film antiferromagnet/ferromagnet layered systems. J. Magn. Magn. Mater. 54–57, 803–804 (1986).
Lee, C. et al. Spin wavepackets in the Kagome ferromagnet Fe3Sn2: propagation and precursors. Proc. Natl Acad. Sci. USA 120, e2220589120 (2023).
Sun, Y. et al. Dipolar spin wave packet transport in a van der Waals antiferromagnet. Materials Cloud Archive https://doi.org/10.24435/materialscloud:9x-ds (2023).
Acknowledgements
We acknowledge the support of the Quantum Materials programme under the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division of the US Department of Energy, contract no. DE-AC02-05-CH11231. J.O and Y.S received support from the Gordon and Betty Moore Foundation’s EPiQS Initiative through grant no. GBMF4537 to J.O. at University of California Berkeley. F.M. and J.Y. acknowledge support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division under contract no. DE-AC02-05-CH11231 (Organic-Inorganic Nanocomposites KC3104). C.L. received support from Hanyang University through startup grant no. HY-202300000001173 and from the National Research Foundation of Korea through grant no. RS-2023-00212540. Z.S. was supported by the ERC-CZ programme (project no. LL2101) from the Ministry of Education Youth and Sports and used large infrastructure from project reg. no. CZ.02.1.01/0.0/0.0/15_003/0000444 financed by the European Regional Development Fund.
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Y.S. and J.O. designed the research. Y.S. carried out all the optical measurements with assistance from C.L. under the supervision of J.O. Bulk crystals were synthesized and characterized by A.S. under the supervision of Z.S. F.M. prepared and characterized thin flakes under the supervision of J.Y. Atomic force microscope measurements were performed by H.Z. and F.M. under the supervision of R.R. Theoretical analysis was performed by Y.S. and J.O. Y.S. and J.O. wrote the paper.
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Supplementary information
Supplementary Information
Supplementary sections 1–12 and Figs. 1–12.
Supplementary Code
Mathematica code to calculate dipolar magnon dispersion in antiferromagnets.
Source data
Source Data Fig. 1
Source data for mode-selective detection of coherent magnons.
Source Data Fig. 2
Source data for detection of coherent magnon propagation.
Source Data Fig. 3
Source data for spin waves in CrSBr.
Source Data Fig. 4
Source data for thickness dependence of magnon group velocity.
Source Data Fig. 5
Source data for signatures of non-linear magnon dispersion.
Source Data Fig. 6
Source data for the range of coherent magnon propagation.
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Sun, Y., Meng, F., Lee, C. et al. Dipolar spin wave packet transport in a van der Waals antiferromagnet. Nat. Phys. (2024). https://doi.org/10.1038/s41567-024-02387-2
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DOI: https://doi.org/10.1038/s41567-024-02387-2
